Not uncommonly, an abdominal CT scan report may say there is thickening of the bowel wall in particular the rectum. The differentials here include:

1. normal bowel wall – perhaps the muscles the wall were contracted at the time of the scan

2. Rectal cancer in particular a circumferential tumour – therefore the next investigation from this is usually a colonoscopy

3. Inflammatory bowel disease, diverticular disease – but one would also see the diverticula etc

An elderly patient was referred with rectal bleeding thought to be from haemorrhoids(The patient has just had colonoscopy <2 years ago by a gastroenterologist which showed only haemorrhoids and was otherwise reported as normal) The patient’s bleeding had not really settled at all since the previous colonoscopy and the patient’s bleeding was attributed to the haemorrhoids reported in the colonoscopy. The patient was referred recently for the haemorrhoidal bleeding and a colonoscopy was performed. A low rectal cancer measuring about 5cm was found(the cancer was arising from a tubulovillous adenoma, located just above the anal canal, the tumour can be felt on rectal examination – mobile, T2 on MRI). Fortunately, this could be treated with a transanal excision of the rectal cancer and the patient recovered quickly from the surgery.

The points to learn from here is that :

1. One should not always assume any rectal bleeding is due to haemorrhoids- especially if this persist despite treatment of the haemorrhoids. (If haemorrhoids have been bleeding up to the colonoscopy, it would be a good idea to band them at the end of the colonoscopy) If symptoms persist, reinvestigate or refer on.

2. A rectal examination is still useful even in the 21st century- As Norman Browse’s book on Symptoms and Signs of Surgical Diseases says “”Every patient with a rectal complaint should have a rectal examination”". This still holds true today. Be thankful that there are gloves these days – I have heard in the past in places where gloves were not easily available, doctors used to put soap into their fingernails before doing the rectal examination. ( A good tip is to double glove the hand doing the rectal examination – that way you can throw away the top glove after the rectal exam before doing anything else)

3. On colonoscopy, care must be taken to look carefully at the anal canal and what is just above. Sometimes faeculent fluid can obscure the view – this should be sucked out. A J manouvre at the end in the rectum is also useful. In fact during my training, I remembered one of my mentors telling me how he heard about a case of a low rectal cancer being missed during a colonoscopydue to too rapid an insertion.

By right, being an investigation, there really should not be such a long wait for a colonoscopy. After all, one of the main reason the test is being done is to exclude a bowel cancer.

Why should a public patient wait for such a long time for an investigation? Does anyone have to wait more than 4 weeks for a blood test or any Xray?

Currently there are so many patients on public waiting lists all over Australia.  Mathematically, I cannot see how this would get any shorter if the current situation persist. In fact, it will only get longer as the population ages, more and more people leave private insurance and hospital budgets become tighter.  Also in public hospitals, the throughtput is much less than in  a private endoscopy centre for a number of reasons including:

1. Hospital bureaucracy slowing turnover of patients

2. Working culture

3. Need for trainee anaesthetists and surgeons/gastroenterlogists to learn hands on

4. Financial model in public hospitals do not given any incentives for the hospital to do more scopes(they would go over budget, they can only have a certain percentage of patients are day cases, and only do a certain number of scopes a year) nor do they give incentives for specialists(paid by the hour on a rate far less than what one gets privately, often moral is low due to hospital bureaucracy, most are staying on only out of a duty to care for their patients and to teach the trainees) to increase throughput

Hence in the public hospitals, the average colonoscopes booked to a half day list(with registrars) may be about 6-7 while privately one can have 8-10 cases on a half day list.(Some private centres do even more than that – but doing  a colonoscopy too quickly is also not good as polyps may be missed.  Ideally, 30min should be allocated for each colonoscopy procedure to allow time to have a careful look on withdrawing the colonoscopy)

Recently another patient in his early 40s went to see his GP for a skin lesion.  The GP suggested he has a FOBT too during the consultation. The FOBT turned out to be positive.  He subsequently had  a colonoscopy which showed a small caecal cancer. He went on to have a right hemicolectomy. Further scans have not shown any evidence of spread.

Were it not for his GP ordering the FOBT, this patient’s cancer would probably not have been detected until a few years later(usually the patient would either present with anaemia; occasionally one can get a right sided abdominal pain  from this that could be the same as an appendicitis type pain). This raises the dilemma for the all doctors  – how aggressively does one screen the patient and from what age? Also is there enough resources to do this especially in the public system?

Frail lady in her eighties presented to her GP with change of bowel action.

Colonoscopy shows 5cm low rectal tumour.

Transanal excision performed – ie surgery via anal canal to resect the tumour alone, not needing a laparotomy.

Histology: Rectal adenoma

How long is it before someone would present with bowel cancer?

This varies from person to person – these days, the sooner one brings this to the doctors attention, the sooner this can be looked at.

Recently a patient in the 70s who has been on holidays travelling around Australia presented to his local GP complaining of a change of bowel action. He was investigated and found to be severely anaemic. He was sent to the Emergency department as he has had increasing difficulty opening his bowels.

On examination, he was found to have a low rectal cancer on rectal examination. Further investigations showed that he has lung metastates.

He went on to have a resection and permanent stoma.

This is a difficult question to answer for the individual.

Just last month a man in his 40s was seeing his GP for a skin problem when the GP suggested that he take the test. The faecal occult blood test came back positive – in fact, positive on all specimen. He was then referred for a colonoscopy.

On colonoscopy, a bowel cancer in the caecum was found.

He subsequently underwent a bowel resection.  The pathology showed that is was a fairly advanced cancer – with lymph glands involved. Further scans suggest the possibility of spread to the liver already..

The main difference is actually the Medicare fees – say you are referred to a specialist because you have been screened for faecal occult blood and the test has been positive. For the initial consult, the Medicare benefits(100%) for the gastroenterologist is $139.45 while for surgeons it is $79.05.  This difference is because different specialities are allowed to claim different rates for the consults and in the past, not many physicians do procedures such as endoscopy.

Also in general, surgeons tend to treat the haemorrhoids at the same time while most gastroenterologist would refer the haemorrhoids to a surgeon for treatment(eg banding of haemorrhoids)

Not all general surgeons do colonoscopies as they concentrate on their specialized fields.  But there are general surgeons too who specializes in colonoscopy.

The most important thing is to check if the endoscopist is allocating enough time to do the scope in order to have a good thorough gentle look for polyps. One can easily miss a polyp in a mucosal fold or under a pool of faeculent fluid if one does a colonoscope too quickly(eg if there are time or economic pressures)

You should always speak to the endoscopist about this. It is best for the endoscopist to allocate on average about 30minutes to do a colonoscopy.

Bowel cancer is so common (About 1 in 20 Australians will develop bowel cancer in their lifetime) and so are haemorrhoids. It is not safe to assume once symptoms is due to haemorrhoids alone. It is best that this is discussed with your general practitioner. And if there are any concerns, you should be referred to a surgeon or endoscopist.

There has certainly the cases where patients present with clear symptoms of bleeding from haemorrhoids but on colonoscopy, a bowel polyp or even bowel cancer has been found!

Faecal Occult Blood Test (FOBT)

What types of FOBT are there?

There are two main types of FOBT – namely the guaiac and immunochemical tests.

The National Bowel Cancer Screening Program uses an immunochemical FOBT called ‘Detect™’.

An immunochemical FOBT is better than a Guaiac FOBTs because they have no potential for interference by diet or medication, and are considered to be less intrusive, more reliable, more acceptable and more likely to achieve higher participation rates.

What does the test involve?

The FOBT is a simple test that can be done at home before sending it to a pathology laboratory for analysis. The test is quick, easy and painless. To increase the chances of detecting tiny amounts of blood in the bowel motion, samples are taken from two separate bowel motions. Because the test involves taking separate samples, it is not practical to do the test at a doctor’s surgery. Once both samples are collected they are returned by post to a pathology laboratory for analysis.

How accurate/effective is the test?

Like any screening test, a FOBT is not 100% accurate. However, it is currently the most well researched screening test for bowel cancer.

Because cancers and precancerous growths only bleed intermittently it is possible that the FOBT will miss one. This is why it is important to screen regularly and see a doctor if symptoms develop, regardless of the FOBT result.

Why do more than one samples need to be provided?

As cancers and precancerous growths only bleed intermittently, providing more than one samples helps to ensure a more accurate FOBT result.

Is a special diet required before collecting the samples?

No. It is not necessary to change your diet in any way.

Are there any restrictions for medication?

No. It is not necessary to avoid taking any medicines before the sample collection. The test is specific for human blood, so the test is not affected by medicines.

Are there any restrictions on when samples cannot be collected?

Yes. Samples cannot be collected if:

• it is during or within 3 days either side of a menstrual period;
• haemorrhoids (piles) are bleeding; or
• blood is present in the urine or visible in the toilet bowl – in this case contact your doctor.

What does the FOBT show?

If no significant blood is found in the samples the FOBT result is negative. People who receive a negative result should repeat a FOBT in two years. If they have or develop symptoms (or become aware of a significant family history of bowel cancer) they should see their doctor as soon as possible.

If significant levels of blood are present in the samples the FOBT result is considered positive. About one in 10 people will have a positive result. The presence of blood may be due to conditions other than cancer, such as polyps, haemorrhoids, or inflammation of the bowel, but the cause of the bleeding needs to be investigated. People with a positive FOBT result will be advised to contact their doctor to discuss the result and should then be referred for a colonoscopy.

An inconclusive or incomplete FOBT result may occur for a number of reasons, including incorrect use of the test, too much faeces in the samples, a significant delay between taking the two samples or a delay in sending the test to the pathology laboratory. The test should be repeated if so.

Reference:

National Bowel Cancer Screening Program

Note:

The second phase of the National Bowel Cancer Screening Program commenced on 1 July 2008 and will only offer testing to people turning 50, 55 or 65 years of age between January 2008 and December 2010. (the reason for this is to ensure waiting times for colonoscopy do not increase dramatically – about 10% of the FOBT are positive requring referral for colonoscopy)

If you are between those ages, please speak to your doctor about getting the screening tests done.